/***************************************************************************
	 FFMpegEncoder.h  -  FFMPEG based video encoder for Piaf
							 -------------------
	begin                : Thu Sep 9 2010
	copyright            : (C) 2010 by Christophe Seyve (CSE)
	email                : cseyve@free.fr
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/

#include "FFMpegEncoder.h"


FFMpegEncoder::FFMpegEncoder(int imageWidth, int imageHeight, int frame_rate) {
	img_convert_ctx = NULL;
	tmp_picture = NULL;
	picture = NULL;

	m_width = imageWidth;
	m_height = imageHeight;
	m_fps = frame_rate;

	fprintf(stderr, "FFMpegEnc::%s:%d create encoder with size %dx%d @ %d fps\n",
			__func__, __LINE__,
			m_width, m_height, m_fps);
}

int FFMpegEncoder::setQuality(int qscale)
{
	if(qscale < 1 || qscale > 31)
		return 0;
	fprintf(stderr, "FFMpegEnc::%s:%d set quality scale = %d\n",
			__func__, __LINE__,
			qscale);

	m_quality = qscale;
	return 1;
}

int FFMpegEncoder::startEncoder(char * output_file) {
	fprintf(stderr, "FFMpegEnc::%s:%d start encoding file '%s'\n",
			__func__, __LINE__,
			output_file);

	int i;

	/* initialize libavcodec, and register all codecs and formats */
	av_register_all();

	strcpy(filename, output_file);

	/* auto detect the output format from the name. default is
	   mpeg. */
	//fmt = av_guess_format(NULL, filename, NULL);
//	fmt = guess_format(NULL, filename, NULL);
//
//	if (!fmt) {
//		printf("Could not deduce output format from file extension: using MJPEG.\n");
//		//fmt = av_guess_format("mjpeg", NULL, NULL);
//		fmt = guess_format("mjpeg", NULL, NULL);
//	}
	fmt = guess_format("mjpeg", NULL, NULL);
	if (!fmt) {
		fprintf(stderr, "Could not find suitable output format\n");
		return 0;
	}

	/* allocate the output media context */
	oc = avformat_alloc_context();
	if (!oc) {
		fprintf(stderr, "Memory error\n");
		return 0;
	}

	// Force format
	oc->oformat = fmt;
	snprintf(oc->filename, sizeof(oc->filename), "%s", filename);


	/* add the audio and video streams using the default format codecs
	   and initialize the codecs */
	video_st = NULL;
	audio_st = NULL;
	if (fmt->video_codec != CODEC_ID_NONE) {
		video_st = add_video_stream(oc, fmt->video_codec);
	}
	if (fmt->audio_codec != CODEC_ID_NONE) {
		audio_st = add_audio_stream(oc, fmt->audio_codec);
	}

	/* set the output parameters (must be done even if no
	   parameters). */
	if (av_set_parameters(oc, NULL) < 0) {
		fprintf(stderr, "Invalid output format parameters\n");
		return 0;
	}

	dump_format(oc, 0, filename, 1);

	/* now that all the parameters are set, we can open the audio and
	   video codecs and allocate the necessary encode buffers */
	if (video_st) {
		fprintf(stderr, "FFMpegEnc::%s:%d open video stream\n",__func__, __LINE__);
		open_video(oc, video_st);
	}
	if (audio_st) {
		fprintf(stderr, "FFMpegEnc::%s:%d open audio stream\n",__func__, __LINE__);
		open_audio(oc, audio_st);
	}

	/* open the output file, if needed */
	if (!(fmt->flags & AVFMT_NOFILE)) {
		fprintf(stderr, "FFMpegEnc::%s:%d open output file\n",__func__, __LINE__);
		if (url_fopen(&oc->pb, filename, URL_WRONLY) < 0) {
			fprintf(stderr, "Could not open '%s'\n", filename);
			return 0;
		}
	}

	/* write the stream header, if any */
	fprintf(stderr, "FFMpegEnc::%s:%d write header\n",__func__, __LINE__);
	av_write_header(oc);

	return 1;
}

void FFMpegEncoder::stopEncoder() {
	/* write the trailer, if any.  the trailer must be written
	 * before you close the CodecContexts open when you wrote the
	 * header; otherwise write_trailer may try to use memory that
	 * was freed on av_codec_close() */
	av_write_trailer(oc);

	/* close each codec */
	if (video_st)
		close_video(oc, video_st);
	if (audio_st)
		close_audio(oc, audio_st);

	/* free the streams */
	for(int i = 0; i < oc->nb_streams; i++) {
		av_freep(&oc->streams[i]->codec);
		av_freep(&oc->streams[i]);
	}

	if (!(fmt->flags & AVFMT_NOFILE)) {
		/* close the output file */
		url_fclose(oc->pb);
	}

	/* free the stream */
	av_free(oc);
	oc = NULL;
};


int FFMpegEncoder::encodeFrameRGB32(unsigned char *RGB32frame) {
	fprintf(stderr, "FFMpegEnc::%s:%d encode frame\n",__func__, __LINE__);
	/* compute current audio and video time */
	if (audio_st)
		audio_pts = (double)audio_st->pts.val * audio_st->time_base.num / audio_st->time_base.den;
	else
		audio_pts = 0.0;

	if (video_st)
		video_pts = (double)video_st->pts.val * video_st->time_base.num / video_st->time_base.den;
	else
		video_pts = 0.0;

	if ((!audio_st || audio_pts >= STREAM_DURATION) &&
		(!video_st || video_pts >= STREAM_DURATION)) {
		fprintf(stderr, "FFMpegEnc::%s:%d error in stream duration\n",__func__, __LINE__);
		return -1;
	}
/*
	if(tmp_picture) {
		fprintf(stderr, "FFMpeg::%s:%d : copy in tmp_picture...\n", __func__, __LINE__);
		tmp_picture->data[0] = RGB32frame;
		tmp_picture->data[1] = tmp_picture->data[1] = NULL;
		tmp_picture->linesize[0] = m_width;
		tmp_picture->linesize[1] = tmp_picture->linesize[1] = 0;
	} else
*/
	{
		fprintf(stderr, "FFMpeg::%s:%d : copy in picture...\n", __func__, __LINE__);
		picture->data[0] = RGB32frame;
		picture->data[1] = picture->data[1] = NULL;
		picture->linesize[0] = m_width*4;
		picture->linesize[1] = picture->linesize[1] = 0;
	}

	/* write interleaved audio and video frames */
	if (!video_st || (video_st && audio_st && audio_pts < video_pts)) {
		write_audio_frame(oc, audio_st);
	} else {
		fprintf(stderr, "FFMpeg::%s:%d : write_video_frame...\n", __func__, __LINE__);
		write_video_frame(oc, video_st);
	}

	return 0;
}



/*
 * add an audio output stream
 */
AVStream * FFMpegEncoder::add_audio_stream(AVFormatContext *oc, enum CodecID codec_id)
{
	AVCodecContext *c;
	AVStream *st;

	st = av_new_stream(oc, 1);
	if (!st) {
		fprintf(stderr, "Could not alloc stream\n");
		exit(1);
	}

	c = st->codec;
	c->codec_id = codec_id;
	c->codec_type = CODEC_TYPE_AUDIO; //AVMEDIA_TYPE_AUDIO;

	/* put sample parameters */
	c->sample_fmt = SAMPLE_FMT_S16;
	c->bit_rate = 64000;
	c->sample_rate = 44100;
	c->channels = 2;

	// some formats want stream headers to be separate
	if(oc->oformat->flags & AVFMT_GLOBALHEADER)
		c->flags |= CODEC_FLAG_GLOBAL_HEADER;

	return st;
}

void FFMpegEncoder::open_audio(AVFormatContext *oc, AVStream *st)
{
	AVCodecContext *c;
	AVCodec *codec;

	c = st->codec;

	/* find the audio encoder */
	codec = avcodec_find_encoder(c->codec_id);
	if (!codec) {
		fprintf(stderr, "codec not found\n");
		exit(1);
	}

	/* open it */
	if (avcodec_open(c, codec) < 0) {
		fprintf(stderr, "could not open codec\n");
		exit(1);
	}

	/* init signal generator */
	t = 0;
	tincr = 2 * M_PI * 110.0 / c->sample_rate;
	/* increment frequency by 110 Hz per second */
	tincr2 = 2 * M_PI * 110.0 / c->sample_rate / c->sample_rate;

	audio_outbuf_size = 10000;
	audio_outbuf = (uint8_t *)av_malloc(audio_outbuf_size);

	/* ugly hack for PCM codecs (will be removed ASAP with new PCM
	   support to compute the input frame size in samples */
	if (c->frame_size <= 1) {
		audio_input_frame_size = audio_outbuf_size / c->channels;
		switch(st->codec->codec_id) {
		case CODEC_ID_PCM_S16LE:
		case CODEC_ID_PCM_S16BE:
		case CODEC_ID_PCM_U16LE:
		case CODEC_ID_PCM_U16BE:
			audio_input_frame_size >>= 1;
			break;
		default:
			break;
		}
	} else {
		audio_input_frame_size = c->frame_size;
	}
	samples = (int16_t *)av_malloc(audio_input_frame_size * 2 * c->channels);
}


/* prepare a 16 bit dummy audio frame of 'frame_size' samples and
   'nb_channels' channels */
void FFMpegEncoder::get_audio_frame(int16_t *samples, int frame_size, int nb_channels)
{
	int j, i, v;
	int16_t *q;

	q = samples;
	for(j=0;j<frame_size;j++) {
		v = (int)(sin(t) * 10000);
		for(i = 0; i < nb_channels; i++)
			*q++ = v;
		t += tincr;
		tincr += tincr2;
	}
}


void FFMpegEncoder::write_audio_frame(AVFormatContext *oc, AVStream *st)
{
	AVCodecContext *c;
	AVPacket pkt;
	av_init_packet(&pkt);

	c = st->codec;

	get_audio_frame(samples, audio_input_frame_size, c->channels);

	pkt.size= avcodec_encode_audio(c, audio_outbuf, audio_outbuf_size, samples);

	if (c->coded_frame && c->coded_frame->pts != AV_NOPTS_VALUE)
		pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
	pkt.flags |= PKT_FLAG_KEY;//AV_PKT_FLAG_KEY;
	pkt.stream_index= st->index;
	pkt.data= audio_outbuf;

	/* write the compressed frame in the media file */
	if (av_interleaved_write_frame(oc, &pkt) != 0) {
		fprintf(stderr, "Error while writing audio frame\n");
		exit(1);
	}
}

void FFMpegEncoder::close_audio(AVFormatContext *oc, AVStream *st)
{
	avcodec_close(st->codec);

	av_free(samples);
	av_free(audio_outbuf);
}

/* add a video output stream */
AVStream *FFMpegEncoder::add_video_stream(AVFormatContext *oc, enum CodecID codec_id)
{
	AVCodecContext *c;
	AVStream *st;

	st = av_new_stream(oc, 0);
	if (!st) {
		fprintf(stderr, "Could not alloc stream\n");
		exit(1);
	}

	c = st->codec;
	c->codec_id = codec_id;
	c->codec_type = CODEC_TYPE_VIDEO; //AVMEDIA_TYPE_VIDEO;

	// Force RGB32 for Qt
	c->pix_fmt = PIX_FMT_RGB32;

	/* put sample parameters */
	c->bit_rate = 400000;
	/* resolution must be a multiple of two */
	c->width = m_width;
	c->height = m_height;

	/* time base: this is the fundamental unit of time (in seconds) in terms
	   of which frame timestamps are represented. for fixed-fps content,
	   timebase should be 1/framerate and timestamp increments should be
	   identically 1. */
	c->time_base.den = STREAM_FRAME_RATE;
	c->time_base.num = 1;
	c->gop_size = 12; /* emit one intra frame every twelve frames at most */
//CSE	c->pix_fmt = STREAM_PIX_FMT;
	if (c->codec_id == CODEC_ID_MPEG2VIDEO) {
		/* just for testing, we also add B frames */
		c->max_b_frames = 2;
	}

	if (c->codec_id == CODEC_ID_MPEG1VIDEO){
		/* Needed to avoid using macroblocks in which some coeffs overflow.
		   This does not happen with normal video, it just happens here as
		   the motion of the chroma plane does not match the luma plane. */
		c->mb_decision=2;
	}
	// CSE :
	if (c->codec_id == CODEC_ID_MJPEG){
	//	c->qmin = c->qmax = m_quality;
	}

	// some formats want stream headers to be separate
	if(oc->oformat->flags & AVFMT_GLOBALHEADER)
		c->flags |= CODEC_FLAG_GLOBAL_HEADER;

	return st;
}

AVFrame * FFMpegEncoder::alloc_picture(enum PixelFormat pix_fmt, int width, int height)
{
	AVFrame *picture;
	uint8_t *picture_buf;
	int size;

	picture = avcodec_alloc_frame();
	if (!picture)
		return NULL;
	size = avpicture_get_size(pix_fmt, width, height);
	picture_buf = (uint8_t *)av_malloc(size);
	if (!picture_buf) {
		av_free(picture);
		return NULL;
	}
	avpicture_fill((AVPicture *)picture, picture_buf,
				   pix_fmt, width, height);
	return picture;
}

void FFMpegEncoder::open_video(AVFormatContext *oc, AVStream *st)
{
	AVCodec *codec;
	AVCodecContext *c;

	c = st->codec;
	// Force RGB32 for Qt
	c->pix_fmt = PIX_FMT_RGB32;


	/* find the video encoder */
	fprintf(stderr, "FFMpegEnc::%s:%d : find the video encoder for "
			"codec id=%d='%s' ...\n",
			__func__, __LINE__,
			c->codec_id, c->codec_name);
	codec = avcodec_find_encoder(c->codec_id);
	if (!codec) {
		fprintf(stderr, "FFMpegEnc::%s:%d : codec id=%d='%s' not found\n",
				__func__, __LINE__,
				c->codec_id, c->codec_name);
		return;
	}

	/* open the codec */
	if (avcodec_open(c, codec) < 0) {
		fprintf(stderr, "FFMpegEnc::%s:%d : could not open codec id=%d='%s' not found\n",
				__func__, __LINE__,
				c->codec_id, c->codec_name);
		return;
	}

	video_outbuf = NULL;
	if (!(oc->oformat->flags & AVFMT_RAWPICTURE)) {
		/* allocate output buffer */
		/* XXX: API change will be done */
		/* buffers passed into lav* can be allocated any way you prefer,
		   as long as they're aligned enough for the architecture, and
		   they're freed appropriately (such as using av_free for buffers
		   allocated with av_malloc) */
		video_outbuf_size = m_width * m_height * 4;
		video_outbuf = (uint8_t *)av_malloc(video_outbuf_size);
	}


	/* allocate the encoded raw picture */
	picture = alloc_picture(c->pix_fmt, c->width, c->height);
	if (!picture) {
		fprintf(stderr, "Could not allocate picture\n");
		return;
	}

	/* if the output format is not YUV420P, then a temporary YUV420P
	   picture is needed too. It is then converted to the required
	   output format */
	tmp_picture = NULL;
	if (c->pix_fmt != PIX_FMT_YUV420P) {
		tmp_picture = alloc_picture(PIX_FMT_YUV420P, c->width, c->height);
		if (!tmp_picture) {
			fprintf(stderr, "Could not allocate temporary picture\n");
			return;
		} else {
			fprintf(stderr, "allocated temporary picture\n");
		}
	}
}

/* prepare a dummy image */
void FFMpegEncoder::fill_yuv_image(AVFrame *pict, int frame_index, int width, int height)
{
	int x, y, i;

	i = frame_index;

	/* Y */
	for(y=0;y<height;y++) {
		for(x=0;x<width;x++) {
			pict->data[0][y * pict->linesize[0] + x] = x + y + i * 3;
		}
	}

	/* Cb and Cr */
	for(y=0;y<height/2;y++) {
		for(x=0;x<width/2;x++) {
			pict->data[1][y * pict->linesize[1] + x] = 128 + y + i * 2;
			pict->data[2][y * pict->linesize[2] + x] = 64 + x + i * 5;
		}
	}
}

void FFMpegEncoder::write_video_frame(AVFormatContext *oc, AVStream *st)
{
	int out_size, ret;
	AVCodecContext *c;

	c = st->codec;

	if (frame_count >= STREAM_NB_FRAMES) {
		/* no more frame to compress. The codec has a latency of a few
		   frames if using B frames, so we get the last frames by
		   passing the same picture again */
	} else {
		if (c->pix_fmt != PIX_FMT_YUV420P) {

			#if 0 // CSE : no need for mjpeg
			/* as we only generate a YUV420P picture, we must convert it
			   to the codec pixel format if needed */
			if (img_convert_ctx == NULL) {
				fprintf(stderr, "FFMpegEnc::%s:%d create sws context\n",__func__, __LINE__);
				img_convert_ctx = sws_getContext(c->width, c->height,
												 PIX_FMT_YUV420P,
												 c->width, c->height,
												 c->pix_fmt,
												 sws_flags, NULL, NULL, NULL);
				if (img_convert_ctx == NULL) {
					fprintf(stderr, "Cannot initialize the conversion context\n");
					exit(1);
				}
			}

			fprintf(stderr, "FFMpeg::%s:%d "
					"sws_scale(img_convert_ctx=%p,"
					" tmp_picture->data={%p, %p, %p}, tmp_picture->linesize={%d,%d,%d},"
					" 0, c->height=%d, picture->data={%p, %p, %p}, picture->linesize={%d,%d,%d});...",
					__func__, __LINE__,
					img_convert_ctx,
					  tmp_picture->data[0], tmp_picture->data[1], tmp_picture->data[2],
					  tmp_picture->linesize[0], tmp_picture->linesize[1], tmp_picture->linesize[2],
					  c->height,
					  picture->data[0], picture->data[1], picture->data[2],
					  picture->linesize[0],picture->linesize[1],picture->linesize[2]
					  );
			fill_yuv_image(tmp_picture, frame_count, c->width, c->height);

			sws_scale(img_convert_ctx,
					  tmp_picture->data, tmp_picture->linesize,
					  0, c->height, picture->data, picture->linesize);
#endif // if 0
		} else {
			//fill_yuv_image(picture, frame_count, c->width, c->height);
		}
	}


	if (oc->oformat->flags & AVFMT_RAWPICTURE) {
		/* raw video case. The API will change slightly in the near
		   futur for that */
		AVPacket pkt;
		av_init_packet(&pkt);

		pkt.flags |= PKT_FLAG_KEY;//AV_PKT_FLAG_KEY;
		pkt.stream_index= st->index;
		pkt.data= (uint8_t *)picture;
		pkt.size= sizeof(AVPicture);

		ret = av_interleaved_write_frame(oc, &pkt);
	} else {
		/* encode the image */
		out_size = avcodec_encode_video(c, video_outbuf, video_outbuf_size, picture);
		/* if zero size, it means the image was buffered */
		if (out_size > 0) {
			AVPacket pkt;
			av_init_packet(&pkt);

			if (c->coded_frame->pts != AV_NOPTS_VALUE)
				pkt.pts= av_rescale_q(c->coded_frame->pts, c->time_base, st->time_base);
			if(c->coded_frame->key_frame)
				pkt.flags |= PKT_FLAG_KEY;//AV_PKT_FLAG_KEY;
			pkt.stream_index= st->index;
			pkt.data= video_outbuf;
			pkt.size= out_size;

			/* write the compressed frame in the media file */
			ret = av_interleaved_write_frame(oc, &pkt);
		} else {
			ret = 0;
		}
	}
	if (ret != 0) {
		fprintf(stderr, "Error while writing video frame\n");
		return;
	}
	frame_count++;
}


void FFMpegEncoder::close_video(AVFormatContext *oc, AVStream *st)
{
	avcodec_close(st->codec);
	av_free(picture->data[0]);
	av_free(picture);
	if (tmp_picture) {
		av_free(tmp_picture->data[0]);
		av_free(tmp_picture);
	}
	av_free(video_outbuf);
}


